Machine for producing air waves



Sept. 10. 1929. w, MAN 1,727,861

MACHINE FOR PRODUCING AIR WAVES A 35 lzuu Filed Nov. 25, 1927 SSheqts-Sheet 1 v 4E8 w 2* 'F 4 J2 Z5 w J i a a i 6 i XX L26 I 3 L Sept. 10, 1929- R. w. CHAPMAN MACHINE FOR PRODUCING AIR WAVES Filed Nov. 25, 1927 .3 Sheets-Sheet 2 A w. w

Sept. 10, 1929.

R. W. CHAPMAN MACHI NE FOR PRODUCING A IR WAVES Filed 192"! 3 Sheets-Shut 3 Patented Sept. 10, 1929.

' UNITED STATES PATENT OFFICE.

RALPH WALLACE CHAI'MAN, OF OLD TOWN, MAINE, ASSIGNOR T0 T. M. CHAPMAN 'S SONS COMPANY, OF OLD TOWN, MAINE, A CORPORATION OF MAINE.

MACHINE FOR PRODUCING AIR WAVES.

' Application filed November as, 1927. Serial No. 235,719.

This invention relates to a machine for producing air waves for use in aural kinesitherapy.

The invention has for its object to produce such air waves by means of an oscillating diaphragm arranged to produce substantially true sinusoidal air waves, and to effect this result by mechanism substantially free from mechanical noise.

A further object is to provide means by which the amplitude of the waves may be varied while maintaining this sinusoidal characteristic.

The invention further relates to the vibrating diaphragm itself, preferably molded from paper pulp, which is light and staff so that it can be directly connected to the connecting rod.

Further, not only the diaphragm, but all moving parts connected therewith are designed so as to be of light weight construction, so that inertia strains on the pivot bearings are minimized.

The invention will be readily understood from the accompanying drawings in which Fig. 1 is a vertical median section through the machine in the plane of line 11, Fig. 2;

Fig. 2 is a plan view, with the cover removed;

Fig. 3 is a sectional plan looking downward, on plane 3-3 of Fig. 1;

Figs. 4 and 5 are sectional details in planes 4-4 and 5-5 of Fig. 2; and

Fig. 6 is. a rear elevation.

The machine comprises a main frame consisting of a base 1, standards 2, 2 and a top plate 3. This main frame carries on pivot pins 4 and 5, a hinged frame, theadjustable pin 4 projecting upwardly from the base 1, and the pin 5 extending downwardly from the top plate 3. This hinged frame has a back portion 6 having a rim or flange extending along its sides and bottom. The bottom flange portion 7, has a bearing for the pivot pin 4, and a cross bar 8, extending from side to side of the hinged frame at its upper portion, has a bearing for the pivot pin 5. The hinged frame and the parts carried by it can be swung from side to side by means of a spring arm 9, secured to the bottom flange portion 7. The arm 9 has a handle 10, and carries at its outer end a screw 11, extending into a slot 12 in the base plate. The arm can be secured in its adjusted position by the nut 13.

The driving motor 14 is mounted on a U- shaped spring plate 15, which is secured at its rear end, as by screws 16 to the bottom flange of a bracket 17 secured by screws 18 to the back plate 6 of the hinged frame. These screws are adjustable in the back plate, as shown in Fig. 6, to permit up and down adjustment of the bracket.

As shown, the motor 14 is supported only at its front end on the spring plate 15, by means of pins 19, extending into socket pieces 20, the rear end being supported by the belt 21 and pulley 22, thus automatically keeping the belt tight. The spring support obviates vibration and noise. At its rear upper portion, the hinged frame carries a bearing support 23, in which is mounted the shaft 24, which at its outer end bears against a hardened thrust bearing 25, having a ball 26 and adjusting screw 27. At its inner end the shaft carries a rotating member having a pulley portion 28 and a balance wheel and crank disk 29, within which is' located, eccentric to the shaft, a fiber bearing 30, backed by a felt pad 31, both perforated to permit flow of oil from the cavity 32. In this hearing is mounted one end of the connecting rod 33 formed as a ball. It will be noted that the pivots 4 and 5 are in the same vertical plane with the axisof shaft 24, and that the center of rotation of the crank disk is also in this plane. The other ball-shaped end of connecting rod 33 is connected to a similar hearing 34 in a yoke shaped member35 (Fig. 4), to which are connected (by bolts 36) at each side leaf springs 37. These leaf springs are pivoted at their lower ends on rod 38, mounted, as shown in Fig. 4, on the supporting bar 39 screwed to the bottom of the lower housing 40. A similar rod 41 having pivot pointed ends is mounted between the upper ends of springs 37; and passes through the oscillator member, here shown as a tube 42. to which the diaphragm 43 is directly secured.

This tube 42 carried atits Inner end on a 100 CJI pivot rod 42, mounted (see Fig. 5) between the upper ends of springs 44, which are connected together by a yoke 46, and mounted at their lower ends on the pivot rod 47, passing through the supporting bar 39. The pivot rods 38, 41, 42' and 47 have hardened conical ends which fit into correspondingly shaped countersunk hearings in the springs. 48, 48

are felt pads to retain oil. The members effected by means of springs 49 attached at one end to a crossbar 50 in tube 42 and at their other ends to an arched stationary mem her 51 secured to housing 40, which is secured by screws 52 to the top plate 3 of the main frame. The rapid to and fro movement of the diaphragm causes the propagation of an air wave whose frequency depends upon the number of revolutions of the crank-shaft 24.

The amplitude of these vibrations is controlled by turning the hinged frame about the pivots, whereby the throw of-the connecting rod is altered to the desired extent.

hen the axes of the rod 42 connected to the diaphragm and of the craft 24 are in the same. plane, as in Figs. 1 and 2, the connecting rod 33 will be rotated, but the front bear-' ing 34 will not be moved. But angular move ment of the hinged frame'about the pivots will change this relation so that the front bearing and the parts connected thereto including the tube 42 and the diaphragm will be given an oscillating movement, the amplitude of which will depend upon the angular movement of the hinged frame. This oscillation will cause the diaphragm to emit a succession of air waves which will be substantially true sinusoidal waves.

The diaphragm is molded in the shape desired, here'shown as semi-spherical, out of paper pulp and is thus extremely light and still, so that it can be supported directly from the oscillator member (tube 42).

The shaft 24 is lubricated by means of the oil cup 24, and the oil works its way along the shaft, and is thrown off into the chamber 32, whence it passes through the oil duct. into the boa ring of the connecting rod and lubricates the ball at. the end of the connecting rod. The ball at the other end of the connecting rod and the pivots of the spring parallel motion are directly lubricated.

A cover )4 generally corresponding in shape to the lower housing 40 is securely clamped thereto by pins 55 at the rear end and an arched spring clamp 56 engaging pins 57. A handle 58 is secured to the lower housing 40.

The operation of the machine is as follows:

The motor drives the crank disk 29, by which through connecting rod 33, an outward rectilinear movement is imparted to the oscillator member 42, mounted on the spring parallel movement, the inward movement being effected by the springs 49. The oscillation of the diaphragm connected to the. oscillator member produces an air wave of substantially pure sinusoidal or simple harmonic form.

The frequency of the wave is determined by the speed of revolution of the motor, and the amplitude of the waves is controlled by variation of the throw of the oscillator member, effected by angular adjustment of the hinged frame carrying the motor and crank disk.

The frequency of the air waves produced by the machine is such that they are themselves substantially inaudible and the construction described minimizes any noise due to mechanical operation. As the waves produccd are of substantially sinusoidal or simple harmonic form the car mechanism of the person within the space in which the air waves are produced is subjected to substantiallyequal increases and decreases in pres- I sure.

I claim: I v

1. A machine for producing air waves comprising a diaphragm mounted for rectilinear oscillation and means for imparting an oscillating movement thereto, said means comprising a motor, a motor driven crank disk and a connecting rod between said disk and the mounting of the diaphragm. i

2. A machine for producing air waves comprising a main frame, a parallel motion device mounted thereon, an oscillator member and diaphragm carried by said parallel motion device, and mechanically operated means for imparting a simple harmonic motion to said oscillator member, said means comprising a motor, a rotary member driven by the mot-or, connections'between said driven member and said oscillator membcr'for imparting from said driven member a positive outward movement to the oscillator member, and resilient means connected to said frame and oscillator member for imparting an inward movement.

3. A machine for producing air waves comprising a main frame, a parallel motion device mounted thereon, an oscillator member and diaphragm carried by said parallel motion device, and mechanically operated means for imparting a simple harmonic motion to said oscillator member, said means comprising a motor, a motor driven crank disk and connecting rod for imparting outward movement to said oscillator member and springs connected to said frame and oseillator member for imparting an inward and a connecting rod between said bearings.

movement.

4. A machine as claimed in claim 3 in si which the motor and crank shaft are mounted on a frame pivoted on the main frame for angular adjustment.

5. A machine for producing air waves comprising a main frame, an oscillator member and diaphragm mounted thereon, and ar-' ranged for oscillatory movement, mechanically operated means for imparting said oscillatory movement comprising a motor, a motor driven crank disk and connecting rod, said mechanically operated means being carried by a separate frame hinged to the main frame for angular adjustment, whereby the throw of the connecting rod may be varied.

6. A machine as claimed in claim 5 in which the motor is supported on a spring plate secured at one end to the hinged frame.

7 A machine as claimed in claim 5 in which the motor drives the crank disk by a. pulley and belt, the front end only of the motor being supported on a spring plate secured at one end to the hinged frame.

8. A machine as claimed in claim 5 in which the hinged frame is provided with means for securing it in adjusted position to the main frame.

9. A machine for producing air waves comprisin a frame, an oscillator member having a diap ragm rigidly connected thereto, a support for said oscillator member comprising a parallel motion having two pairs of spring members pivoted at their lower ends to the main frame and pivoted at their upper ends to rods connected to the oscillator member, a motor, a rotary member driven by the motor, connections between said driven member and said oscillator member for imparting from said driven member a positive outward movement to the oscillator member, and resilient means connected to said frame and oscillator member for imparting an inward movement.

10. A machine as claimed in claim 9 in which each pair of spring members is braced by a yoke connection, and a connecting rod bearing on the front pair of spring members.

11. A machine for producing air waves comprising a main frame and a separate frame hinged thereto, the hinged frame having mounted thereon a spring supported m0- tor and a belt driven crank shaft and crank disk provided with a bearing for a connecting rod; the main frame having mounted thereon an oscillating member having a diaphragm rigidly connected thereto, a support for said oscillating member comprising a parallel motion having two pairs of spring members pivoted at their lower ends to the main frame and pivoted at their upper ends to rods connected to the oscillating member. a bearing for a connecting rod on one pair of spring members, springs connected to the main frame and to the oscillating member In testimony whereof I have atiixed my gnature. 

